Electric call or signal



LE R. S. WHITE.

ELECTRIC CALL on SIGNAL.

Patented Aug. 2, 1881,.

(Model.)

NITED STATES APATENT raten.

ELECTRIC CALL OR SIGNAL.

SPECIFICATION forming part of Letters Patent No. 245,249, dated August2, 1881.

Application filed May 19, 1880. (Model.)

To all whom it may concern v Be it known that I, LE Rov S. WHITE, ofWaterbury, in the county of New Haven and State of Connecticut, haveinvented certain new and useful Improvements in Electric Calls orSignals, of which the following is a specication.

Although my improvements may be embodied in electric calls for variouspurposes, they are particularly adapted for use in connection withtelephone-lines to permit any one instrument of a number of instrumentslocated" upon one line to be called from the central otiice withoutcalling all the instruments. y

In carrying out myinvention I use at the central station two batteriesof unequal strength or a battery composed ot two portions, one of whichmay be used separately, or both of which may be combined, or I may useas the equivalent any other means ot producing a weak and strongcurrent. These batteries or their equivalents are connected with a linepassing through the several stations, and at each station is a branchcircuit containing a' bell.

My invention consists in the combination, with such means ot' producinga weaker and a stronger current, and with such lineand branch circuits,of an instrument at each station on the line operated by said batteries,and coniprising an electro-magnet with a single armature which is movedunequal distances by the weaker and stronger currents, and certain meanscombined with the armature of said magnet whereby the armature may bemade to close the branch circuit ot' the instrument which it is desiredto call, and no others on the line. I employ at each station, inconnection with one of said magnets and armatures, a stop for saidarmature, which may consist of a spring ot' sufficient strength toresist the weak current, but which will be overcome by the strong'current and permit a further movementot the armature. I also employ, inconnection with the above, a ratchet-wheel and a dent-wheelconstituting` a signal-controlling device, so connected that whileimpulses imparted to the ratchet-wheel will cause them both to moveforward against the resistance of springs or weights constitutingseparate and independent retractors, the ratchet-wheel itself upon beingreleased is free to' returnby the force ofthe spring or weightindependently of the dent-wheel. The armature or an arm projectingtherefrom carries a pawl, by which the ratchet-wheel is moved Aforwardstep by step a single tooth for each impulse imparted by the weakcurrent, a stop-pawl being employed to hold the ratchet after each weakimpulse. 'When actuated, however, bya strong current the armature andarm carrying the pawl are moved farther forward, and the pawl bysuitable devices is raised into contactwith the stop-pawl, disengagingit from the ratchetwheel and permitting the latter to be moved by theretractive force of the spring or'weight back to its starting-pointagainst a stop provided forit. At the same time that the ratchetwheel isreleased a tooth or dent upon the arm carrying the pawl engages with thesaid dentwheel and blocks or holds the latter stationary, while itprevents the arm from movingt'ar enough to close the short circuit, inwhich a bell is situated. Each dent-wheel or signalcontrolling device isconstructed with a stop flange or rim in which is a single deep notch,and in the dent-wheels at the several stations or instruments thesenotches are arranged to correspond with the successive teeth ot' theratchet-wheels. Vlien the deep vnotch'in the dent-wheel orsignal-controlling device comes opposite the tooth in the pawl-carryinglever, a strong current will cause afull movementot' the armature andpawl-carr 7ing arm, and by it close the short circuit in which the bellis situated, and sound the bell. Inasmuch, however, as the'deep notch inthe dent-wheels at the other stations do not come opposite the teeth onthe pawlcarrying arms ofthe several instruments, other bells will not besounded. It being known, therefore, at the central station with whichtooth ot' the ratchet-wheels the deep notch in each den t-'wheelcorresponds, all that is necessary is to actuate the armature by asuccession ot' weak currents to bring the deep notch in the dent-wheelot that station opposite the tooth on the pawl-carrying arm, and then bya strong current release all the ratchet-wheels simultaneously,permitting them to return to the starting-point, and causing the toothof the pawl-carrying arm at the desired station to enter the notch inthe dent- IOO wheel and close the bell-circuit. Inasmuch as only thestation with which communication is desired is called, an ordinaryvibrating bell may be used with advantage.

The construction and opera-tion of the several parts of myinventionhereinabove referred to will be fully and clearly described hereinafter.

In the accompanying drawings, Figure l represents a side view of myimproved instrument, partially in section, to more clearly show theconstruction, and embracing a diagram ot' the battery, bell, andconductors. Fig. 2 represents a side view ot' a portion of theinstrument, showing the manner ot' releasing the ratchet-wheel to permitits return to the starting-point. Fig. 3 represents a face view of theratchet and dent wheels and the stop-pawl and supporting-frame. Fig. 4represents a detail sectional view of the ratchet and dent wheels, andFig. 5 represents a transverse section on the line x w, Fig. 4.

Similar letters ot' reference designate corresponding parts in all thetigures.

A designates an electro-magnet, and B the armature thereof, pivoted ata.

C designates an arm secured to the armature, projecting` upwardtherefrom and swinging or oscillating with the armature as the latter isattracted by an electric current passing through the magnet A.

D designates aratchet-wheel, preferably having teeth upon a portion ofits periphery only; and D designates a pawl carried by the arm C, andserving as a means of actuating the ratchet-wheel by a step-by-stepmovement. This ratchet-wheel is mounted upon a fixed shaft or pivot, l),supported in a frame-work, A, fixed upon a standard, A2, projectingupward from the base-board A3 of the instrument. The said ratchet-wheelis iitted to revolve freely upon the spindle b, and is moved by the pawlD against the force of a retractor consisting of a coiled spring, c,fixed at one end to the spindle b and at the other end to the rim of thewheel, which is made hollow, so as to contain the spring within it.

D2 designates a stop-pawl bearing on the wheel D and holding it againstthe force of the spring c, which exerts a constant force to impel thewheel backward.

It' a weak current be passed through the magnet A the armature is drawnforward .until a spring, C', arranged at the back of the arm C strikesagainst an abutment, d, projecting from the frame A', thus forming ayielding stop having power to resist the weak current passing throughthe magnet A. By this partial movement of the arm C the pawl D has beencaused to move the ratchet-wheel D one tooth ahead, where it is retainedby the stop-pawl D2. Any numbergof weak currents passed through themagnet will, it is evident, move the ratchet-wheel forward acorresponding number of teeth.

Upon the spindle or shaft b, upon which the ratchet-wheel D rotates,is atoothed or notched dent-wheel, E, also fitting loosely upon the shat'tb, and containing within it a spring, e, attached and actuating thedent-wheel in a similar manner to the spring c in the wheel D. Thoughsprings for actuating the wheels D and E are here shown as being mostdesirable, weights might be used in lieu thereof. By turning the spindleor shaft b the springs c and c may be either tightened or weakened, soas to exert more or less power on the wheels D and E.

As here shown clearly in Figs. et and 5, the dent-wheel E derives itsforward movement from the ratchet-wheel D, and therefore the two must beconnected by a clutch which will permit the backward movement of thesaid ratchet-wheel independently ofthe dent-wheel.

The dent-wheel, which, as above stated, constitutes a signal-controllingdevice, is moved back independently ot' the ratchet-wheel by a separateretractor composed of its spring c.

rllhe clutch here shown consists ofapin or stud f, projecting from theratchet-wheel D, and engaging with an arc-shaped recess, g, in thedent-wheel, as shown clearly in Fig. 5. As both the wheels have aconstant tendency in a backward direction, imparted to them by theirindependent retractors, the ratchet-wheel cannot move forward withoutimparting an equal movement tothe dent-wheel, and consequently theforward movement of both wheels is produced by the pawl D.

The dent-wheel E has upon one side of its teeth a stop-flan ge or rim,h, only slightly smaller in diameter than the cxtremediameter ofthewheel, the teeth ofthe wheel consequently projecting slightly beyond theface of the rim. The office of this rim or flange will be hereinafterexplained. If, now, a strong current be passed through the magnet A,thearmature and arm C will receive an impulse sufciently stron g toovercome the resistance ot' the spring-stop C', and the arm movingfarther than usual will cause the pawl D/ to strike against an abutment,i, by which the pawl will be raised out of contact with the teeth of theratchet-wheel D, as shown clearly in Fig. 2, and at the same time anextensiomj, ot' said pawl coming in contact with the under side of thestop-pawl D2 will raise the latter, thus leavin g the said wheel free toturn back under the impulse ot' the spring c until the last tooth of thewheel strikes a stop, 7c, projecting inward from the side of the frameA', thus making a definite starting-point for the ratchet-wheel. By theforward movement ot' the arm C under the strong current a tooth, l, uponsaid arm is brought into engagement with the dent-wheel and against therim or stop-flan ge h, thus precluding further movement of the arm C andarmature B.

By reference to Figs. 4 and 5 it will be seen that in the edge or faceof the rim or iiange h is a sin gle deep notch, m, and it is obviousthat in case this notch comes opposite the tooth l lOO IZO

it will receive said tooth, and permit the full movement of the armatureand arm C.

From the frame A', which is in the short bell-circuit, there projects acontact-point, n, and by the full movement of the armature and arm G aknob or boss, o, of insulating material, which bears upon a spring-nger, p, constituting a part of said short bell-circuit, presses the saidfinger against the contact-point n, closes the bell-circuit, and causesthe ringing of the bell, as more fully hereinafter described. One of myinstruments being placed at each station along the telephone-line, aswell {as at the central station, a series of weak currents will causeall the ratchet-wheels D to be advanced simultaneousl'ytooth by tooth,and with them the several dent-wheels will be correspondingly movedforward.

The deep notch min each dent-wheel should be adjusted to correspond withone of the teeth ofthe ratchet-wheels, and to afford provision for suchadjustment the rim or stop-fian'ge h of the dent-wheel E is composed ot'a ring fitting upon the hub of the wheel, and held in place by frictionafter being adjusted by turning it upon the hub ofthe said wheel.

As it is necessary that there should always be a weak current passedbefore a strong one, so as to insure the proper adjustment of theinstrument, the notch m in the dent-wheel at the first station should bein such a position relatively to the teeth of the ratchet-wheel thatwhen at the starting-point one strong impulse will call station 1, aweak and a strong impulse will call station 2, two weak and one strongimpulses will call station 3, three weak and one strong` impulses willcall station 4, and so on in succession, the number of teeth in theratchet-wheels being one more at least than the number of stations.

The notches m at the several stations being properly and permanently1adjusted, the operation is as follows: It' it is desired to call stationNo. 3, the armature is actuated three times by the weak current movingall the ratchet-wheels forward three teeth and the dent wheels acorresponding distance. A strong currentis now passed through themagnet, giving still another impulse to the ratchet and dent wheels. andholding the latterfixed by the teeth l, while the ratchet-wheels are allmoved backward to the starting-point by their springs c. lt is obviousthat inasmuch as the notch m in the dent-wheel' of station No. 3 isopposite the tooth Z, the armature of that instrument may complete itsfull movement, making contact ofthe spring-iingerp with the contactpoint a, closing the bell-circuit, and ringing the bell at the stationNo. 3. Inasmuch, however, as the notches in the stop flanges of theother dent-wheels are not opposite the teeth l, all the other armaturesare prevented from making their full movement, andhencenone of the otherstations are called. If the tooth l struck simply against the face ofthe rim or stop-Harige h, the latter, under the impulse of the spring e,might slip so as to bring its notch m against the tooth l and produce afalse ring; but inasmuch as the tooth l enters between the teeth ofthedent-wheel E, such an accident is impossible.

Having thusdescribed the construction and operation of the instrumentitself, I will now describe the battery and arrangement of conductorswhereby weak or strong currents are produced at will and the bellsounded.

The battery represented is composed ot' two portions, F F', from one orboth ot which the circuit may be made through keys G G', and branchconductors H H', to the main conductor I, leading to the magnet A. Whenonly a weak current is desired the key G is operated and the portionF'ofthc battery is cnt out of the circuit; but when a strong current isdesired the key G'is operated and the combined strength ot' bothportions of the battery utilized. The ordinary course ot' the currentfor charging the magnet A is through the conductor I to thebinding-postJ; thencethrough the conductor K to and through the magnetto the binding-post L, and thence back through the return-comluctorM tothe other pole ofthe battery.

The branch circuit for operating the bell is shown bydotted lilies, andthe current passes from the binding-post J through the conductor N tothe fra-me A' and contact-point n; thence, theA circuit being closed,through the iingerp andconductor O to the binding-post P; thence throughthe conductor Q to and through the bell R (preferably of vibratingaction) and through the conductor S to the binding-post L. When theshort bell-circuit is closed a sufficient amount of electricity will bedrawn from the main current to sound the bell, leaving, however, asufficient quantity to hold the armature B against the magnet A.

The central office can be called when desired by breaking circuit in theusual way, the number of thestation being indicated by the number oftimes the bell is sounded.

In case any of the instruments may have been tampered with and theratchet and dent wheels turned forward, it may be advisable, beforesounding a call, to give a succession ot' weak impulses one more innumber than the number of stations, and then a strong TOO IOS

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impulse, which will turn the wheels of all the instruments back to thestarting-point without ringing any bell.

I do not broadly claim the ratchet-wheel having a step-by-step movementgiven to it by the armature of an electro-magnet and thesignal-controlling device adapted to be moved positively with said wheelin such step-by-step movement, but to allow the said wheel to move backindependently of said device. Nor do I claim, broadly, the ratchet-wheeland retractor therefor and mechanism to give the said wheel astep-by-step forward movement, combined with a signal-controlling deviceadapted to be engaged at a certain point by IZO Uli

and moved forward positively with said wheel, and an independentretractor for said device, whereby, after said wheel and device havebeen lnoved forward together, the wheel may be released and moved backindependently of said device, and the latter, when released, will belnoved to its pointof' engagement with said wheel; but

lhat I claim as my invention, and desire to secure by Letters Patent,is-

1. The combination of the magnet A, the armature B, arm C, spring G',and abutment d, substantially as specified.

2. The combination, in an electric-call apparatus, of a ratchet-wheeland a spring or weight for producing a backward movement thereof, meansfor producing a weak .current for actuating said ratchet-wheel againstthe force of the spring or weight, a dent-wheel connected with theratchet-wheel by a clutch connection and rotated thereby, and mechanismto be actuated by a strong current for simultaneously leleasin g saidratchet-wheel and blocking said dent-wheel, substantially as specified.

3. The combination, in an electric-call apparatus, of' a series ofinstruments at several stations each comprising a ratchet-wheel providedwith a spring or weight for producing the backward movement, and adent-wheel operated from said ratchet-wheel, means at one station forproducing a weak current for rotating said wheels, and mechanismactuated by a strong current for simultaneously releasing all theratchet-wheels and blocking all the dent-wheels, substantially asspecified.

4. The combination,iu an electric-call apparatas, of' a ratchet-wheel, aspring or weight for producing a backward movement thereof', adent-wheel connected with said ratchet-wheel by a clutch-connection androtated thereby, a stop-pawl for holding said ratchet against the springor weight, a magnet, an armature and attached arm, a pawl carried bysaid arm which, by a weak current through the magnet, moves said wheelsforward, and which, by a strong current, raises the stop-pawl andreleases said ratchet, and a tooth carried by said arm, which engageswith and blocks the dentwheel when the armature is actuated by a strongcurrent, substantially as specified.

5. The combination, in an electric-call apparatus, of a ratchet-wheeland spring or weight for producing a backward movement thereof, a magnetand armature, and an arm attached to said armature and carrying acircuit-closing device, mechanism operated by said armature and soconnected with the ratchet that the latter may be moved forward by aweak current and released by a strong current through the magnet, a dent-wheel moved forward by the ratchetv and having a rim or fiange inwhich is a notch, a spring or weight for producing the backward movementof said dent-wheel, and a tooth which, by a strong current through themagnet, is caused to eugage with and block said dent-wheel, and whichmay enter said notch to permit the said armature and attached arm tomove suciently f'a'r to close the electric circuit, substantially asspecified.

6. The combination, in an electric-call apparatus, of the ratchet-wheelD and dent-wheel E, having a notch, on, in its rim or flange, a clutchconnecting said wheels, the springs c and c, and the stop lr, allsubstantially as specified.

7. The combination of the dent-wheel E and the loose fiange or rimh,fitting upon the hub of said wheel and having a notch, m, in itsperiphery, substantially as specified.

S. The combination of the ratchet-wheel D, dent-wheel E, having a notch,m, in its rim or iiange, a clutch connecting said wheels, the springs cc, the magnet A, armature B, arm C, pawls D' D?, and the tooth or dentl, all arranged and operated substantially as specified.

9. The combination, in an electric-call apparatus, of an electro-magnet,a battery comprising two portions, and a line-wire or conductor, all soarranged that a current may be' passed from one or both portions of thebattery through the line and magnet, an armature, an arm attached tosaid armature and carrying a device for closing a branch circuitcontaining a call, a dent-wheel having a notched stop-flange and meansfor rotating thc same, and a tooth carried by said arm and adapted toenter the notch in the stop-flange of the dent-wheel, so as to permitthe closing of said branch circuit, substantially as specified.

l0. The combination, in an electric-call :1pparatus, of' a main circuit,a short branch circuit containing an electric bell, the magnet A in themain circuit,A the armature B, and arm C, and the contact-point u andspring-finger p, forming part of said branch circuit, substanA tially asspecified.

LE ROY S. WHITF.

Witnesses Unas. W. GILLET'rE, DAVID S. PLUME.

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